v0.8.2

Changed

• Restored Claude as the unset default backend for implementation executors and daemon supervisors while keeping explicit Codex configuration supported.
• Updated packaged Galley plugins to 0.1.17 with stronger task-authoring proof guidance, clearer reference-file responsibilities, and language-neutral examples.
• Improved runtime executor, setup, and acceptance-skeleton prompts for AC proof-detail handling and language-neutral examples.